This invention relates to conveyor chain and, more particularly, to an improved conveyor chain for use in a product capturing conveyor.
Product capturing chains have been used in the past for elevating articles from one level to another in a conveyor system. Many companies currently design machines for conveying articles during manufacture, labeling, etc. One such particular machine is a rinsing machine (or xe2x80x9crinserxe2x80x9d) of many configurations and designs (for example, xe2x80x9chigh-in/low-outxe2x80x9d shown in FIG. 1 and xe2x80x9clow-in/low-outxe2x80x9d shown in FIG. 2 configurations, elevator/lowerator machines, and head space sterilizer machines). The disclosure herein will describe this invention with particular reference to a rinser. However, it is an intention herein to utilize the technology disclosed herein not only across the entire family of rinsing machines, but in all areas of conveyance machines and in other areas where movement along a conveyor line is useful.
It is known in the art to manufacture rinsers which are designed to rinse bottles with water and/or ionized air in preparation for being filled. The basic mode of operation involves receiving bottles from a standard tabletop conveyor or an air conveyor in a single file orientation and then gripping the bottles with dual strands of a xe2x80x9cgripper chainxe2x80x9d (for example a Rexnord LF1873G gripper chain) or similar gripper chains running parallel to each other. Once in the rinser, the bottles are inverted while held by the chains by riding along large diameter curved tracks or turning wheels and then being subjected to multiple streams of water and/or ionized air while in an inverted position. Inverting the bottle allows contaminants as well as any water being used in the process to exit the bottle via the opening in the bottle top. The bottles remain inverted in the rinsing machine for distances of up to 20 ft. to allow water to completely drain from the bottle before being turned upright again at the opposite end of the machine. The bottles are returned to the upright position in the same manner in which they were inverted, with a second set of turning wheels or curved tracks at the opposite end of the machine. The bottles exit the rinser in a single file orientation upon being released by the rinser gripper chain to standard tabletop conveyors or air conveyors.
With particular reference to FIG. 3, inherent to the function of inverting bottles 100 with turning wheel 12 is the geometric problem involved in the inversion. As the chain follows the contour of the turning wheel 12, the vertical centerlines 14 of the bottles 100 align themselves to point at the axis of rotation (i.e., center point) of the turning wheel 12. And because bottles 100 are gripped/constrained at about their midpoint during movement around the turning wheel 12, the distance between their vertical centerlines increases at points further from the center point of the turning disc 12 and decreases at points nearer the center point of the turning wheel 12. Therefore, if bottles 100 enter the rinser xe2x80x9cbody-to-bodyxe2x80x9d (aligned touching each other with vertical centerlines parallel), the portion of the bottles 100 closer to the center point of the tuning disc will interfere with one another causing crunching, denting, or damage as shown in FIG. 3. FIG. 4 shows a chain wherein the portion of chain closer to the center point of turning wheel 12 creates a xe2x80x9ccontraction zonexe2x80x9d and the portion of chain further from the center point of turning wheel 12 creates a xe2x80x9cexpansion zonexe2x80x9d.
The prior art attempts to avoid such damage by xe2x80x9cmeteringxe2x80x9d the bottles before they enter the rinser. Metering supplies a space or gap between the bottles as they enter the rinser (xe2x80x9cgappingxe2x80x9d). Providing space between the bottles as they enter the rinser allows the bottles to progress through the turning disc and not interfere with each other in the xe2x80x9ccontraction zonexe2x80x9d. However, gapping the bottles creates several undesirable conditions in the functioning of the machine. Such undesirable conditions include requiring metering equipment, increasing the running speed of the rinser to compensate for the gaps between bottles, and wasting water/air between the gaps in the bottles.
The present invention seeks to eliminate the undesirable conditions caused by xe2x80x9cgappingxe2x80x9d in conventional rinsers or other conveyance machines by providing an improved conveyor chain having movable grippers that move in a direction relative to the axis of rotation of a turning wheel or relative to the center point of a curved track (defined by the curved track""s radius of curvature) to provide clearance for bottles as they travel around the turning wheel or curved track.
The present invention provides a chain link having a movable gripper where the chain link comprises a carrier member having a top portion and a gripper slidably engaged with the top portion of said carrier member. The carrier member has a bottom portion that includes means for supporting the chain link on a track. The top portion of the carrier body includes a groove that extends along at least a portion of the length of the carrier member. The gripper includes a base portion having a corresponding tongue to engage the groove in the carrier member. Alternatively, the gripper includes a base portion having a groove that extends along at least a portion of the base portion of the gripper. Hence, the top portion of the carrier member has a corresponding tongue that extends along at least a portion of the length of the carrier member to engage the groove in the base portion of the gripper.
In another embodiment, a conveyor system for moving articles comprises a conveyor including a chain having a plurality of links that follows a track defining a travel path. The travel path includes a curved portion having a radius of curvature defining a center point. Each link has a gripping member in sliding engagement with the link wherein the gripping member is movable relative to the link. Each link includes means for supporting the link in said track wherein the link follows the travel path of the track. The chain includes a proximal portion that is closer to the center point of the curved portion and a distal portion that is farther from the center point of the curved portion wherein the proximal portion defines a contraction zone and the distal portion defined an expansion zone when the chain travels around the curved portion. The conveyor system includes means means for moving each gripping member into the expansion zone before each respective link travels along the curved portion of said track.
The present invention also provides for a conveyor system comprising a conveyor including a chain having a plurality of links that follows a track defining a travel path. The track includes a curved portion such a turning wheel or curved track having a radius of curvature defining a center point. Each link includes means for supporting the link in the track wherein the link follows the travel path of the track. Each link also includes a gripping member that is in sliding engagement with the link wherein the gripping member is movable relative to the link. The conveyor system further comprises an urging mechanism positioned along the track to move each gripping member in a direction relative to the center point of the curved portion when each gripping member reaches the urging mechanism. The urging mechanism may comprise a guide bar to move the gripper member in a direction relative to the track and/or relative to the center point of the curved portion. Preferably, the guide bar is positioned along a portion of the track before the curved portion to move the gripper members in a direction away from the center point of the curved thereby moving the gripping members entirely in the expanded zone prior to reaching the curved portion of the track. This will ensure that no xe2x80x9cbottle crunchingxe2x80x9d takes place as the bottles travel around the curved surface. The guide bar may extend around the perimeter of the curved portion of the track to maintain the gripper member in the expanded position. The urging mechanism may comprises a cam positioned adjacent the curved portion of the track and the gripping member defines the cam follower. Alternatively, a member may extend from the gripper defining the cam follower.
There are several advantages of this invention as compared to conventionally designed rinsers. Most notable is the reduction in running speed of the rinser as a result of eliminating the gaps between bottles, which allows the rinser to achieve the same throughput at a lower chain speed. The lower running speed results in lower wear on machine components and reduced maintenance downtime and costs. In addition, the elimination of the need to create gaps between bottles results in the elimination of requiring metering equipment prior to bottles entering the rinser. Another advantage of this invention is better rinsing of the bottles due to the slower speed of the bottles through the rinsing area. The lack of gaps between the bottles also results in a reduction in the amount of water and/or air required to rinse the bottles and the costs associated with supplying these, as well as a reduction in the amount water drained reducing associated sewage costs.